Ribbon guide for typewriter ribbon cartridge

ABSTRACT

A ribbon guide or carrier arm for a typewriter ribbon cartridge is disclosed. The carrier arm which is pivotally connectable to the cartridge housing to laterally extend therefrom, has a pair of channels formed therein for guiding a ribbon from the housing to a print point and back to the housing. An aperture is provided adjacent the end of the arm for exposing a portion of the ribbon to the print point. The end of the arm is V-shaped to effect a reversal in the direction of movement of the ribbon. A step having channel means therein for the ribbon is provided at the opening to the V-shaped section. A transparent plastic sheet is secured over the channels in the carrier arm guiding the ribbon and a hollow V-shaped cap is secured over the end of the carrier arm thus shielding most of the ribbon along the carrier arm outside the housing.

United States Patent 11 1 1111 3,777,871 Zeamer 1 1 Dec. 11, 1973 RIBBON GUIDE FOR TYPEWRITER 3,643,779 2/1972 Anderson et a1. 197/151 RIBBON CARTRIDGE [75] Inventor: Aaron C. Zeamer, Groton, N.Y. [73] Assignee: SCM Corporation, New York, N.Y.

22 Filed: May 3, 1972 1 71 AB TRA T [21] Appl. No.: 249,954 A ribbon guide or carrier arm for a typewriter ribbon cartridge is disclosed. The carrier arm which is pivotaily connectable to the cartridge housing to laterally Primary Examiner-Ernest T. Wright, Jr. Attorney-Milton Wolson et a1.

US. Cl. extend therefrom has a pair of channels formed therein for a ribbon from the housing to a 1 Fleld of Search 1 153 R, 153 A, print point and back to the housing. An aperture is 197/157, 158, 159, 170, 162, 168; 101/336 provided adjacent the end of the arm for exposing a portion of the ribbon to the print point. The end of the [56] Rderences (med arm is V-shaped to effect a reversal in the direction of UNITED STATES PATENTS movement of the ribbon. A step having channel means therein for the ribbon is provided at the opening to the 3,643,777 2/1972 Anderson et a1. 197/151 2,869,705 1/1959 Gates 197/151 P sectlon- A transparent Plasuc Sheet 15 623,502 4/ 1899 De1a Mar 197/151 cured over the channels in the carrier arm guiding the 809,378 ,1/1906 Kay 197/170 UX ribbon and a hollow V shaped cap is secured over the 2,464,042 3/ 1.949 inskeep 101/336 d f the arrier arm thus hielding most of the rib- 2,883,029 4/1959 Gray 197/162 hon along the carrier arm outside the housing. 3,590,221 6/1971 Malkowski. 197/168 UX 3,643,778 2/1972 Anderson 197/151 13 Claims, 4 Drawing Figures PATENTED DEC 1 1 I975 SHEET 10F 2.

RIBBON GUIDE FOR TYPEWRITER RIBBON CARTRIDGE BACKGROUND OF THE INVENTION The present invention relates to ribbon guide or carrier arms for typewriter ribbon cartridges of the type having a housing and a carrier arm laterally extending therefrom to guide a ribbon from the housing to a print point in the typewriter and thereafter return the ribbon to the housing. More specifically, the present invention relates to carrier arms for use in ribbon cartridges of the type disclosed in U.S. Pat. No. 3,643,777 entitled TYPEWRITER RIBBON CARTRIDGE and U.S. Pat. No. 3,643,779 entitled RIBBON MECHANISM FOR CARTRIDGE SUPPORTED RIBBONS both granted on Feb. 22, 1972 and U.S. Pat. application Ser.No. 150,946 filed June 9, 1971 entitled TYPEWRITER RIBBON CARTRIDGE all assigned to the assignee of the instant application.

Ribbon cartridges and other devices for typewriters or like printing machines have been provided to assist in the installation of ribbons into such machines and to minimize the soiling of fingers during such process. In addition, such cartridges and devices have been found helpful in increasing the lifespan of the ribbons and the uniformity of printing by shielding the ribbon from exposure to environmental elements. In this connection, a recent advance in the art of typewriter ribbon cartridges has been the development of typewriter ribbon cartridges of the type disclosed in the above referred to patent applications assigned to the present assignee. These cartridges employ a housing for a supply of ribbon and a ribbon guide carrier arm laterally extending from the housing for guiding the ribbon from the housing to a print point within the typewriter and back to the housing. These cartridges are insertable in the typewriter to a position where the arm is engaged by a lift mechanism in the typewriter. Thus, there is no need for threading of the ribbon nor other manipulations which are time consuming and cause soiling of the fingers. Furthermore, the cartridges are removable by sliding the cartridge from the typewriter thus enabling easy replacement or variation in color or type of ribbon, e.g. carbon ribbon or fabric ribbon.

In cartridges of the above type, the guide or carrier arm must define a path for the flow of ribbon which offers little resistance to the flow and which insures against snagging. The guide must also minimize sagging of the ribbon which could cause the ribbon going to the print point and that coming from it to rub against each other and thus disturb the flow of ribbon as well as reduce its lifespan by removing ink therefom. In addition, the guide or carrier arm should be shielded to protect the ribbon from environmental elements. All of this must be accomplished and still permit the easy thread- SUMMARY OF THE INVENTION The present invention consists of a ribbon guide or carrier arm for a typewriter ribbon cartridge of the type having a housing for a supply of ribbon and a ribbon guide or carrier arm laterally extending therefrom to guide the ribbon from the housing to the print point and back to the housing. The carrier arm which is pivotably connectable to the housing is provided with an elongated section having a pair of channels formed therein for guiding the ribbon and a shield plate to assist in said guiding as well as to protect the ribbon from exposure to environmental conditions. Adjacent the elongated section is an aperture for threading the ribbon through the carrier arm and additional guide means which guide the ribbon to an aperture to be positioned adjacent this print point in the typewriter for exposing the ribbon for printing. Following the print point aperture is a V-shaped section for reversing direction of flow of the ribbon. The entrance to the V-shaped section has a step or shoulder extending therearound with channels therein to permit entry of the ribbon. A hollow V-shaped cap is provided to engage the step and shield the ribbon.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a partial perspective view of a typewriter having a cartridge thereon employing the ribbon guide or carrier arm of the instant invention;

FIG. 2 is a rear perspective view of the ribbon guide or carrier'arm showing its pivotal connection to the cartridge;

FIG. 3 is a front perspective view of the ribbon guide or carrier arm with the ribbon shields removed showing how the ribbon is guided along and threaded through the carrier arm; and

FIG. 4 is an exploded perspective view of the ribbon guide or carrier arm of the instant invention.

DETAILED DESCRIPTION OF THE INVENTION Having generally described the instant invention a more detailed description will now be given of a preferred embodiment thereof with specific reference to FIGS. 1-4.

Referring initially to FIG. 1, the ribbon guide or carrier arm 10 is shown laterally extending from a typewriter ribbon cartridge 12 of the type described in the above referred to patent applications assigned to the present assignee. The cartridge 12 is insertable into the typewriter 14 to a point where a stud 16 on the carrier arm 10 engages a lever 18 of a lift mechanism 20. The carrier arm 10 has an aperture 22 therein which is aligned behind typebar guide 24 to expose a portion of the ribbon 26 to a typing element. During a typing operation the lift mechanism 20 lifts carrier arm 10 raising ribbon 26 to a point adjacent the print point indicated generally at 27 of the typewriter 14 where the ribbon 26 is struck by a typing element to transfer an inked character to the paper or other record medium.

Referring next to FIGS. 2-4, the carrier arm 10 is pivotally mounted on the cartridge 12 by a stud 28 which rests on fulcrum 30. A spring 32 has one end thereof extending through aperture 34 in the fulcrum 30 to remain secure to the cartridge 12 and its opposite end engages the hook-like tab 36 on the carrier arm 10 to retain the carrier arm 10 in position biased counterclockwise in the view of FIG. 3 to a rest position which maintains the carrier arm 10 at the correct orientation to engage lever 18 of the lift mechanism 20 during insertion of the cartridge 12 in the typewriter 14.

The carrier arm 10 has an elongated body 38 having flanges 40 and 42 extending therealong. Situated between flanges 40 and 42 and parallel thereto is partition 44. Partition 44 is shorter than the portions of flanges 40 and 42 directly opposite it. Flanges 40 and 42 and partition 44 thus provide channels 44a and 44b for the flow of ribbon 26. Aperture 46 is provided permitting ribbon 26 to pass to the rear side of carrier arm 10.

The rear side of carrier arm 10 is provided with flanges 48 and 50 and partition 52. In addition, a guide and retaining finger 54 is provided projecting upward from the partition 52 and thick enough to extend partially into a window 53. Flanges 48 and 50, partition 52 and guide finger 54 guide the ribbon 26 to and from print point aperture 22.

The end of carrier arm 10 has a V-shaped end or section 54a and has a teat-like projection 55 on the end thereof. At the mouth of the V-shaped section 54a of the carrier arm 10 is a flange, step, or shoulder 56 which extends around the carrier arm l and has channels therethrough at 56a and 56b separated by a partition 57. The channels 56a and 56b define a path for the ribbon 26 which enters the V-shaped section 54a of the carrier arm 10, goes around the legs of the V-shaped section 54a and leaves the V-shaped section 54a.

A first shield in the form of a cover plate 58 (see FIG. 4) is provided for shielding the ribbon 26 along the carrier arm as well as retaining the ribbon 26 in the channels 44a and 44b. Cover plate 58 has an aperture therein at 60 and partition 44 has a hook-like finger 62 thereon. In addition, a shoulder or abutment 64 is provided on the carrier arm 10 facing the opening of the hook-like finger 62. Thus, the cover plate 58 is secured to the carrier arm 10 by placing it over the hook-like finger 62 to have the latter extend through the aperture 60 and sliding the cover plate 58 to the right until its end 59 falls behind and abuts abutment 64 which prevents its accidental removal.

A second shield is provided in the form of a hollow V-shaped cap 66 which is mounted upon the step or shoulder 56 to permit the entry and departure of the ribbon 26 to and from the V-shaped section 54a of the carrier arm 10 without adding to the friction on the ribbon 26. An aperture 67 is provided in cap 66 to receive teat-like projection 55 to align the cap 66 on the carrier arm 10 and prevent ribbon 26 from snagging or riding over the end of the carrier arm 10. Finger 54 and cap 66 cooperate to retain the upper portion of ribbon 26 against movement perpendicular to the plane of the carrier arm 10 as well as against movement transverse to the flow of ribbon 26 in order to insure uniform smudgefree typing.

Since the shields 58 and 66 are easily placed on the carrier arm 10 after threading of the ribbon 26, they do not interfere with the threading operation.

In the preferred embodiment of the instant invention all of the parts of the carrier arm 10 are plastic with the exception of the V-shaped cap 66 which is preferably metal so that it may be pinched onto the end of the carrier arm 10. In addition, the cover plate 58 maybe made transparent if desired to make the ribbon 26 visible whereby indicia such as indication of the end of the ribbon 26 may be seen on the ribbon 26. While the instant invention has been described with respect to a preferred embodiment thereof, many modifications thereof will now become apparent to those of ordinary skill in the art. Thus, it is desired that the scope of the invention not be limited by the foregoing illustrative description but rather by the appended claims.

What is claimed is:

1. An improved cartridge for a typewriter ribbon, the cartridge having an arm with a V-shaped end to change the direction of the ribbon substantially degrees, wherein the improvement comprises a flange around a portion of the mouth of the V of the V-shaped end of the arm to guide the ribbon on one face of the V and a channel for the ribbon on the other face of the V substantially perpendicular to and through the flange.

2. The cartridge of claim 1 which includes a hollow V-shaped cap mounted on the flange on the V-shaped end of the arm, the cap providing clearance for movement of the ribbon to, around, and away from the end of the arm while confining the ribbon on the end of the arm and shielding the ribbon.

3. The cartridge of claim 2 which includes a projection on the point of the V of the V-shaped end of the arm and an aperture for the projection in the point of the V of the V-shaped cap to align the cap on the end of the arm and prevent the ribbon from riding over the end of the arm.

4. The cartridge of claim 1 'which includes a partition in the channel to form two substantially parallel channels for the'ribbon.

5. The cartridge of claim 4 which includes a hollow V-shaped cap mounted on the flange on the V-shaped end of the arm, the cap providing clearance for movement of the ribbon to, around, and away from the end of the arm while confining the ribbon on the end of the arm and shielding the ribbon.

6. The cartridge of claim 5 which includes a projection on the point of the V of the V-shaped end of the arm and an aperture for the projection in the point of the V of the V-shaped cap to align the cap on the end of the arm and prevent the ribbon from riding over the end of the arm.

7. The cartridge of claim 1 which includes a second channel for the ribbon in an intermediate portion of the arm on the opposite side of the arm from the channel in the V-shaped end but in alignment with the channel in the V-shaped end, a hook-like finger in the second channel dividing the second channel into two substantially parallel channels for the ribbon, and a shield having an aperture for mating with the hook-like finger to connect the shield to the arm over the second channel while allowing clearance for movement of the ribbon in the two substantially parallel channels of the second channel.

8. The cartridge of claim 7 which includes an abutment on the arm for the end of the shield on the openend side of the hook-like finger to lock the shield on the arm.

9. The cartridge of claim 8 which includes a partition in the second channel to divide the second channel into said twosubstantially parallel channels for the ribbon and the hook-like finger is on the partition.

10. The cartridge of claim 9 in which the shield is composedof'a transparent material to permit viewing of the ribbon.

11. An improved cartridge for a typewriter ribbon, the cartridge having an arm, wherein the improvement comprises a channel for the ribbon in an intermediate 12. The cartridge of claim 1 l which includes a partition in the channel to divide the channel into said two substantially parallel channels for the ribbon and the hooklike finger is on the partition.

13. The cartridge of claim 12 in which the shield is composed of a transparent material to permit viewing of the ribbon. 

1. An improved cartridge for a typewriter ribbon, the cartridge having an arm with a V-shaped end to change the direction of the ribbon substantially 180 degrees, wherein the improvement comprises a flange around a portion of the mouth of the V of the V-shaped end of the arm to guide the ribbon on one face of the V and a channel for the ribbon on the other face of the V substantially perpendicular to and through the flange.
 2. The cartridge of claim 1 which includes a hollow V-shaped cap mounted on the flange on the V-shaped end of the arm, the cap providing clearance for movement of the ribbon to, around, and away from the end of the arm while confining the ribbon on the end of the arm and shielding the ribbon.
 3. The cartridge of claim 2 which includes a projection on the point of the V of the V-shaped end of the arm and an aperture for the projection in the point of the V of the V-shaped cap to align the cap on the end of the arm and prevent the ribbon from riding over the end of the arm.
 4. The cartridge of claim 1 which includes a partition in the channel to form two substantially parallel channels for the ribbon.
 5. The cartridge of claim 4 which includes a hollow V-shaped cap mounted on the flange on the V-shaped end of the arm, the cap providing clearance for movement of the ribbon to, around, and away from the end of the arm while confining the ribbon on the end of the arm and shielding the ribbon.
 6. The cartridge of claim 5 which includes a projection on the point of the V of the V-shaped end of the arm and an aperture for the projection in the point of the V of the V-shaped cap to align the cap on the end of the arm and prevent the ribbon from riding over the end of the arm.
 7. The cartridge of claim 1 which includes a second channel for the ribbon in an intermediate portion of the arm on the opposite side of the arm from the channel in the V-shaped end but in alignment with the channel in the V-shaped end, a hook-like finger in the second channel dividing the second channel into two substantially parallel channels for the ribbon, and a shield having an aperture for mating with the hook-like finger to connect the shield to the arm over the second channel while allowing clearance for movement of the ribbon in the two substantially parallel channels of the second channel.
 8. The cartridge of claim 7 which includes an abutment on the arm for the end of the shield on the open-end side of the hook-like finger to lock the shield on the arm.
 9. The cartridge of claim 8 which includes a partition in the second channel to divide the second channel into said two substantially parallel channels for the ribbon and the hook-like finger is on the partition.
 10. The cartridge of claim 9 in which the shield is composed of a transparent material to permit viewing of the ribbon.
 11. An improved cartridge for a typewriter ribbon, the cartridge having an arm, wherein the improvement comprises a channel for the ribbon in an intermediate portion of the arm, a hook-like finger in the channel dividing the channel into two substantially parallel channels for the ribbon, a shield having an aperture for mating with the hook-like finger to connect the shield to the arm over the channel while allowing clearance for movement of the ribbon in the substantially parallel channels, and an abutment on the arm for the end of the shield on the open-end side of the hook-like finger to lock the shield on the arm.
 12. The cartridge of claim 11 which includes a partition in the channel to divide the channel into said two substantially parallel channels for the ribbon and the hook-like finger is on the partition.
 13. The cartridge of claim 12 in which the shield is composed of a transparent material to permit viewing of the ribbon. 